A → black hole of tremendous mass, equivalent to those of
millions or even billions of stars, which is believed to exist and occupy the centers
of many galaxies. The supermassive black hole residing in the center of our
→ Milky Way Galaxy is
the object → Sgr A* with a mass of 4 x 106→ solar masses within a radius of 100
→ astronomical units.

A star with an initial mass over about 120 solar masses.
The existence of such stars is the present Universe is not confirmed.
Such stars were proposed as an explanation for very bright O type stars in the Large Magellanic
Cloud, but these are now known to be clusters of ordinary O stars.
→ very massive star;
→ massive star.